[PATCH] mv643xx_eth: Refactor/clean up tx queue handling
Signed-off-by: Dale Farnsworth <dale@farnsworth.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/mv643xx_eth.c b/drivers/net/mv643xx_eth.c
index 260be80..8a24b39 100644
--- a/drivers/net/mv643xx_eth.c
+++ b/drivers/net/mv643xx_eth.c
@@ -62,6 +62,9 @@
#define WRAP HW_IP_ALIGN + ETH_HLEN + VLAN_HLEN + FCS_LEN
#define RX_SKB_SIZE ((dev->mtu + WRAP + 7) & ~0x7)
+#define ETH_RX_QUEUES_ENABLED (1 << 0) /* use only Q0 for receive */
+#define ETH_TX_QUEUES_ENABLED (1 << 0) /* use only Q0 for transmit */
+
#define INT_UNMASK_ALL 0x0007ffff
#define INT_UNMASK_ALL_EXT 0x0011ffff
#define INT_MASK_ALL 0x00000000
@@ -333,49 +336,78 @@
netif_device_attach(dev);
}
-/*
- * mv643xx_eth_free_tx_queue
+/**
+ * mv643xx_eth_free_tx_descs - Free the tx desc data for completed descriptors
*
- * Input : dev - a pointer to the required interface
- *
- * Output : 0 if was able to release skb , nonzero otherwise
+ * If force is non-zero, frees uncompleted descriptors as well
*/
-static int mv643xx_eth_free_tx_queue(struct net_device *dev,
- unsigned int eth_int_cause_ext)
+int mv643xx_eth_free_tx_descs(struct net_device *dev, int force)
{
struct mv643xx_private *mp = netdev_priv(dev);
- struct net_device_stats *stats = &mp->stats;
- struct pkt_info pkt_info;
- int released = 1;
+ struct eth_tx_desc *desc;
+ u32 cmd_sts;
+ struct sk_buff *skb;
+ unsigned long flags;
+ int tx_index;
+ dma_addr_t addr;
+ int count;
+ int released = 0;
- if (!(eth_int_cause_ext & (BIT0 | BIT8)))
- return released;
+ while (mp->tx_desc_count > 0) {
+ spin_lock_irqsave(&mp->lock, flags);
+ tx_index = mp->tx_used_desc_q;
+ desc = &mp->p_tx_desc_area[tx_index];
+ cmd_sts = desc->cmd_sts;
- /* Check only queue 0 */
- while (eth_tx_return_desc(mp, &pkt_info) == ETH_OK) {
- if (pkt_info.cmd_sts & BIT0) {
+ if (!force && (cmd_sts & ETH_BUFFER_OWNED_BY_DMA)) {
+ spin_unlock_irqrestore(&mp->lock, flags);
+ return released;
+ }
+
+ mp->tx_used_desc_q = (tx_index + 1) % mp->tx_ring_size;
+ mp->tx_desc_count--;
+
+ addr = desc->buf_ptr;
+ count = desc->byte_cnt;
+ skb = mp->tx_skb[tx_index];
+ if (skb)
+ mp->tx_skb[tx_index] = NULL;
+
+ spin_unlock_irqrestore(&mp->lock, flags);
+
+ if (cmd_sts & BIT0) {
printk("%s: Error in TX\n", dev->name);
- stats->tx_errors++;
+ mp->stats.tx_errors++;
}
- if (pkt_info.cmd_sts & ETH_TX_FIRST_DESC)
- dma_unmap_single(NULL, pkt_info.buf_ptr,
- pkt_info.byte_cnt,
- DMA_TO_DEVICE);
+ if (cmd_sts & ETH_TX_FIRST_DESC)
+ dma_unmap_single(NULL, addr, count, DMA_TO_DEVICE);
else
- dma_unmap_page(NULL, pkt_info.buf_ptr,
- pkt_info.byte_cnt,
- DMA_TO_DEVICE);
+ dma_unmap_page(NULL, addr, count, DMA_TO_DEVICE);
- if (pkt_info.return_info) {
- dev_kfree_skb_irq(pkt_info.return_info);
- released = 0;
- }
+ if (skb)
+ dev_kfree_skb_irq(skb);
+
+ released = 1;
}
return released;
}
+static void mv643xx_eth_free_completed_tx_descs(struct net_device *dev)
+{
+ struct mv643xx_private *mp = netdev_priv(dev);
+
+ if (mv643xx_eth_free_tx_descs(dev, 0) &&
+ mp->tx_ring_size - mp->tx_desc_count >= MAX_DESCS_PER_SKB)
+ netif_wake_queue(dev);
+}
+
+static void mv643xx_eth_free_all_tx_descs(struct net_device *dev)
+{
+ mv643xx_eth_free_tx_descs(dev, 1);
+}
+
/*
* mv643xx_eth_receive
*
@@ -547,15 +579,13 @@
*/
mv_write(MV643XX_ETH_INTERRUPT_CAUSE_REG(port_num),
~eth_int_cause);
- if (eth_int_cause_ext != 0x0)
+ if (eth_int_cause_ext != 0x0) {
mv_write(MV643XX_ETH_INTERRUPT_CAUSE_EXTEND_REG
(port_num), ~eth_int_cause_ext);
-
- /* UDP change : We may need this */
- if ((eth_int_cause_ext & 0x0000ffff) &&
- (mv643xx_eth_free_tx_queue(dev, eth_int_cause_ext) == 0) &&
- (mp->tx_ring_size - mp->tx_desc_count > MAX_DESCS_PER_SKB))
- netif_wake_queue(dev);
+ /* UDP change : We may need this */
+ if (eth_int_cause_ext & (BIT0 | BIT8))
+ mv643xx_eth_free_completed_tx_descs(dev);
+ }
#ifdef MV643XX_NAPI
} else {
if (netif_rx_schedule_prep(dev)) {
@@ -596,14 +626,13 @@
if (mii_link_ok(&mp->mii)) {
mii_ethtool_gset(&mp->mii, &cmd);
mv643xx_eth_update_pscr(dev, &cmd);
+ mv643xx_eth_port_enable_tx(port_num,
+ ETH_TX_QUEUES_ENABLED);
if (!netif_carrier_ok(dev)) {
netif_carrier_on(dev);
- if (mp->tx_ring_size - mp->tx_desc_count >
- MAX_DESCS_PER_SKB) {
+ if (mp->tx_ring_size - mp->tx_desc_count >=
+ MAX_DESCS_PER_SKB)
netif_wake_queue(dev);
- /* Start TX queue */
- mv643xx_eth_port_enable_tx(port_num, mp->port_tx_queue_command);
- }
}
} else if (netif_carrier_ok(dev)) {
netif_stop_queue(dev);
@@ -735,9 +764,6 @@
mp->rx_used_desc_q = 0;
mp->rx_desc_area_size = rx_desc_num * sizeof(struct eth_rx_desc);
-
- /* Enable queue 0 for this port */
- mp->port_rx_queue_command = 1;
}
/*
@@ -779,9 +805,6 @@
mp->tx_used_desc_q = 0;
mp->tx_desc_area_size = tx_desc_num * sizeof(struct eth_tx_desc);
-
- /* Enable queue 0 for this port */
- mp->port_tx_queue_command = 1;
}
static int mv643xx_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
@@ -963,25 +986,14 @@
static void mv643xx_eth_free_tx_rings(struct net_device *dev)
{
struct mv643xx_private *mp = netdev_priv(dev);
- unsigned int port_num = mp->port_num;
- unsigned int curr;
- struct sk_buff *skb;
/* Stop Tx Queues */
- mv643xx_eth_port_disable_tx(port_num);
+ mv643xx_eth_port_disable_tx(mp->port_num);
- /* Free outstanding skb's on TX rings */
- for (curr = 0; mp->tx_desc_count && curr < mp->tx_ring_size; curr++) {
- skb = mp->tx_skb[curr];
- if (skb) {
- mp->tx_desc_count -= skb_shinfo(skb)->nr_frags;
- dev_kfree_skb(skb);
- mp->tx_desc_count--;
- }
- }
- if (mp->tx_desc_count)
- printk("%s: Error on Tx descriptor free - could not free %d"
- " descriptors\n", dev->name, mp->tx_desc_count);
+ /* Free outstanding skb's on TX ring */
+ mv643xx_eth_free_all_tx_descs(dev);
+
+ BUG_ON(mp->tx_used_desc_q != mp->tx_curr_desc_q);
/* Free TX ring */
if (mp->tx_sram_size)
@@ -1062,30 +1074,6 @@
}
#ifdef MV643XX_NAPI
-static void mv643xx_tx(struct net_device *dev)
-{
- struct mv643xx_private *mp = netdev_priv(dev);
- struct pkt_info pkt_info;
-
- while (eth_tx_return_desc(mp, &pkt_info) == ETH_OK) {
- if (pkt_info.cmd_sts & ETH_TX_FIRST_DESC)
- dma_unmap_single(NULL, pkt_info.buf_ptr,
- pkt_info.byte_cnt,
- DMA_TO_DEVICE);
- else
- dma_unmap_page(NULL, pkt_info.buf_ptr,
- pkt_info.byte_cnt,
- DMA_TO_DEVICE);
-
- if (pkt_info.return_info)
- dev_kfree_skb_irq(pkt_info.return_info);
- }
-
- if (netif_queue_stopped(dev) &&
- mp->tx_ring_size - mp->tx_desc_count > MAX_DESCS_PER_SKB)
- netif_wake_queue(dev);
-}
-
/*
* mv643xx_poll
*
@@ -1099,7 +1087,7 @@
#ifdef MV643XX_TX_FAST_REFILL
if (++mp->tx_clean_threshold > 5) {
- mv643xx_tx(dev);
+ mv643xx_eth_free_completed_tx_descs(dev);
mp->tx_clean_threshold = 0;
}
#endif
@@ -1156,11 +1144,9 @@
{
int tx_desc_curr;
- tx_desc_curr = mp->tx_curr_desc_q;
-
BUG_ON(mp->tx_desc_count >= mp->tx_ring_size);
- mp->tx_desc_count++;
+ tx_desc_curr = mp->tx_curr_desc_q;
mp->tx_curr_desc_q = (tx_desc_curr + 1) % mp->tx_ring_size;
BUG_ON(mp->tx_curr_desc_q == mp->tx_used_desc_q);
@@ -1180,7 +1166,6 @@
int frag;
int tx_index;
struct eth_tx_desc *desc;
- struct net_device_stats *stats = &mp->stats;
for (frag = 0; frag < skb_shinfo(skb)->nr_frags; frag++) {
skb_frag_t *this_frag = &skb_shinfo(skb)->frags[frag];
@@ -1205,7 +1190,6 @@
this_frag->page_offset,
this_frag->size,
DMA_TO_DEVICE);
- stats->tx_bytes += this_frag->size;
}
}
@@ -1215,21 +1199,21 @@
* Ensure the data for an skb to be transmitted is mapped properly,
* then fill in descriptors in the tx hw queue and start the hardware.
*/
-static int eth_tx_submit_descs_for_skb(struct mv643xx_private *mp,
- struct sk_buff *skb)
+static void eth_tx_submit_descs_for_skb(struct mv643xx_private *mp,
+ struct sk_buff *skb)
{
int tx_index;
struct eth_tx_desc *desc;
u32 cmd_sts;
int length;
- int tx_bytes = 0;
+ int nr_frags = skb_shinfo(skb)->nr_frags;
cmd_sts = ETH_TX_FIRST_DESC | ETH_GEN_CRC | ETH_BUFFER_OWNED_BY_DMA;
tx_index = eth_alloc_tx_desc_index(mp);
desc = &mp->p_tx_desc_area[tx_index];
- if (skb_shinfo(skb)->nr_frags) {
+ if (nr_frags) {
eth_tx_fill_frag_descs(mp, skb);
length = skb_headlen(skb);
@@ -1244,7 +1228,6 @@
desc->byte_cnt = length;
desc->buf_ptr = dma_map_single(NULL, skb->data, length, DMA_TO_DEVICE);
- tx_bytes += length;
if (skb->ip_summed == CHECKSUM_HW) {
BUG_ON(skb->protocol != ETH_P_IP);
@@ -1276,9 +1259,9 @@
/* ensure all descriptors are written before poking hardware */
wmb();
- mv643xx_eth_port_enable_tx(mp->port_num, mp->port_tx_queue_command);
+ mv643xx_eth_port_enable_tx(mp->port_num, ETH_TX_QUEUES_ENABLED);
- return tx_bytes;
+ mp->tx_desc_count += nr_frags + 1;
}
/**
@@ -1306,7 +1289,8 @@
spin_lock_irqsave(&mp->lock, flags);
- stats->tx_bytes = eth_tx_submit_descs_for_skb(mp, skb);
+ eth_tx_submit_descs_for_skb(mp, skb);
+ stats->tx_bytes = skb->len;
stats->tx_packets++;
dev->trans_start = jiffies;
@@ -1893,7 +1877,7 @@
MV643XX_ETH_PORT_SDMA_CONFIG_DEFAULT_VALUE);
/* Enable port Rx. */
- mv643xx_eth_port_enable_rx(port_num, mp->port_rx_queue_command);
+ mv643xx_eth_port_enable_rx(port_num, ETH_RX_QUEUES_ENABLED);
/* Disable port bandwidth limits by clearing MTU register */
mv_write(MV643XX_ETH_MAXIMUM_TRANSMIT_UNIT(port_num), 0);
@@ -2602,79 +2586,6 @@
}
/*
- * eth_tx_return_desc - Free all used Tx descriptors
- *
- * DESCRIPTION:
- * This routine returns the transmitted packet information to the caller.
- * It uses the 'first' index to support Tx desc return in case a transmit
- * of a packet spanned over multiple buffer still in process.
- * In case the Tx queue was in "resource error" condition, where there are
- * no available Tx resources, the function resets the resource error flag.
- *
- * INPUT:
- * struct mv643xx_private *mp Ethernet Port Control srtuct.
- * struct pkt_info *p_pkt_info User packet buffer.
- *
- * OUTPUT:
- * Tx ring 'first' and 'used' indexes are updated.
- *
- * RETURN:
- * ETH_OK on success
- * ETH_ERROR otherwise.
- *
- */
-static ETH_FUNC_RET_STATUS eth_tx_return_desc(struct mv643xx_private *mp,
- struct pkt_info *p_pkt_info)
-{
- int tx_desc_used;
- struct eth_tx_desc *p_tx_desc_used;
- unsigned int command_status;
- unsigned long flags;
- int err = ETH_OK;
-
- spin_lock_irqsave(&mp->lock, flags);
-
- BUG_ON(mp->tx_desc_count < 0);
- if (mp->tx_desc_count == 0) {
- /* no more tx descs in use */
- err = ETH_ERROR;
- goto out;
- }
-
- /* Get the Tx Desc ring indexes */
- tx_desc_used = mp->tx_used_desc_q;
-
- p_tx_desc_used = &mp->p_tx_desc_area[tx_desc_used];
-
- BUG_ON(p_tx_desc_used == NULL);
-
- command_status = p_tx_desc_used->cmd_sts;
- if (command_status & (ETH_BUFFER_OWNED_BY_DMA)) {
- /* Still transmitting... */
- err = ETH_ERROR;
- goto out;
- }
-
- /* Pass the packet information to the caller */
- p_pkt_info->cmd_sts = command_status;
- p_pkt_info->return_info = mp->tx_skb[tx_desc_used];
- p_pkt_info->buf_ptr = p_tx_desc_used->buf_ptr;
- p_pkt_info->byte_cnt = p_tx_desc_used->byte_cnt;
- mp->tx_skb[tx_desc_used] = NULL;
-
- /* Update the next descriptor to release. */
- mp->tx_used_desc_q = (tx_desc_used + 1) % mp->tx_ring_size;
-
- BUG_ON(mp->tx_desc_count == 0);
- mp->tx_desc_count--;
-
-out:
- spin_unlock_irqrestore(&mp->lock, flags);
-
- return err;
-}
-
-/*
* eth_port_receive - Get received information from Rx ring.
*
* DESCRIPTION: